Clam-shell dredger.



S. 0. SMITH. CLAM SHELL DREDGER. APPLIGATION FILED MAY 6, 1911.

Patented Feb. 27, 1912.

SAMUEL CHAfiIiES SMITH, {3F DAISY, LOUISIANA.

chem-sum nannena.

Specification of Letters Patent.

Patented Feb, 2'7, MHZ,

Application flied May 6, 1911. Serial No. 625,546.

To all whom it may concern:

Be it known that I, SAMUEL C. Smrn, a

citizen of the United States of America,

and a resident of Daisy, in the parish of Plaquemines, State ofLouisiana, have invented certain new and useful Improve ments inClam-Shell Dredgers, of which the following is a full and clearspecification, reference being had to the accompanying drawings, inwhich- Figure 1 is a vi w partlyin side elevation and partly in verticalsection; Fig. 2 is a perspective view showing the parts connected withthe upper edges of the scoops; and Fig. 3 a detail plan of the rods forsupporting the drums.

The object of this invention is to provide a simple means whereby theact of raising the scoop or dredger will cause the buckets to close andgather up the load and the act of lowering will conversely open thebuckets or scoops to a position to properly enter the material orarticles to be elevated, as more fully hereinafter set forth. I

In the drawing, a; designates a frame to the lower end of which a seriesof four shells or scoops b is pivotally hung by means of a series ofdepending links bL- Each scoop is provided with an arm 0 extendinginwardly and pivotally connected to a knob or ball 0? rigidly attachedto the lower end of a screw 6. This screw rod 0 extends upwardly to nearthe upper part of the frame and is threaded through a sleeve nut mountedro'tatably upon a cross bar 9 of the frames and provided at its lowerend with a bevel gear h. At opposite sides of the screw rod is mounted apair-0f gear wheels 2' each having affixed to its outer face a drum j.These gear wheels 2' mesh with the gear wheel. 7t and they and theirdrum are loosely mounted upon horizontal rods 7c. The outer ends ofthese rods is are rigidly fastened to the side bars of the frame andtheir inner ends are rigidly fastened to an open frame ring Zsurrounding the screw rod and thus adapted to support the inner ends ofthe rods in Wound onthe drums in opposite directions are the lower endsof cables m, these cables passing up through a ring or hole 71 in thetop of the frame a. v

v In lowering the device, the weight of the device is allowed to comeentirely on one of the cables m while the other cable is slacked up; theeffect of this is to cause the taut cable to unwind and rotate its drum,and the rotation of this drum causes gear h and the other gear 71 to berotated, whereupon the slack cable is wound up on its drum and the screwis forced downwardly to the position shown in dotted lines to open thescoops or shells. The weight of the apparatus will cause the shells orscoops to enter the material or articles to be elevated; and then uponraising the device by means of the other cable, e. the cable which waspermitted to run slack in lowering, the apparatus, the screw will beturned in the opposite direction to close the shells or scoops and thelowering cable will be wound up again on its drum or pulley.

Having thus described my invention,.fwl1at claim as newand desire tosecure by Letters hatent, is zcombination, a frame, a rotatable nutvertically mounted in th eframe and provided with a beveled gear at oneend and having its other end held against movement upwardly ordownwardly, a vertical screw extending through said nut and havingthreaded engagement therewith, shafts supported in the frame at rightangles to said screw, drums on said shafts each provided with a beveledgear meshing with thegear carried by the nut, oppositely woundsuspending cables respectively attached to said drums, scoops pivotallyattached to the lower end of said screw and means for pivotallysuspending them from the frame.

in testimony whereof I hereunto afiix my signature in the presence oftwo'witnesses.

SAMUEL CHARLES SMITH. Witnesses:

Cnsnnns A. Vos'r, J12, MILTON Hines.

